1. Field of the Invention.
Cargo security seals for shipping enclosures transported by rail, highway, air or marine facilities. The object of such security seals is to combat cargo theft and pilferage.
2. Description of Prior Art.
The closest patent art known to applicant is U.S. Pat. No. 3,602,538, issued to Gilbert Canter on Aug. 31, 1971 for a Padlock Seal. This patent shows a padlock seal which is intended to perform substantially the same purpose as is performed by the present invention. However, the patented padlock seal is a relatively expensive device, consisting of a number of component parts requiring pre-assembly by the manufacturer. It is not economically conducive to use as a disposable seal.
The present invention is related, in principle, to applicant's invention which is described and claimed in his co-pending patent application, Ser. No. 267,517, filed concurrently herewith. The title of applicant's co-pending case is Keyless Padlock Seal. In both cases the hasp is spring-locked to the lock body. In the co-pending case it is the hasp itself which is spring-biased, and no separate spring element is required to interlock the hasp with the lock body. In the present case, on the other hand, a spring element, separate and apart from the hasp, is provided between the hasp and the lock body. It is this spring element which in the present case spring-locks the hasp to the lock body.